A process for producing concrete is known in the art using, as an aggregate, fine barkhan sands (cf. O. A. Gershberg "Technology of Concrete and Reinforced-Concrete Articles", Moscow, Strojizdat Publishing House, 1971). This process contemplates production of concrete by mixing cement, barkhan sand and water in specified proportions.
The process is rather simple, but concrete produced thereby feature a low mechanical strength due to a high specific surface area of the sand.
Another process is known in the art for the production of concrete, wherein sand is first screened to fractions and then enriched with fractions having larger particle size. Thereafter sand is mixed with cement and water (cf. Yu. M. Bazehenov "Methods for determination of composition of concrete of different kinds", Moscow, Strojizdat Publishing House, 1975). This process has a limited application, since it contemplates the use of sands having only large-size fractions. Furthermore, concrete produced by this process has a high bulk mass and an insufficient mechanical strength.
A process for producing a light-weight concrete, is known in the art wherein a large-size aggregate: crushed stone, gravel is first prepared. To this end, burnt and dump rocks are crushed and intermixed with a plastic clay and coal at the following proportions of the components, percent by weight:
dump rock: 8 to 25 PA1 burnt rock: 50 to 72 PA1 plastic clay: 12 to 27 PA1 coal: 3 to 9 PA1 loess: 90 to 94 PA1 ground apatite: 3 to 7 PA1 liquid fuel: 3 PA1 barkhan sand: 95 to 30 PA1 fuel: 3 to 20 PA1 plastic binder: 2 to 60;
The thus-prepared charge is granulated, roasted, crushed and screened. Thereafter, the resulting material is mixed with cement and water (cf. I. A. Ivanov "Technology of light-weight concretes with artificial porous aggregates", Moscow, Strojizdat Publishing House, 1974).
The use is also known of loess in the charge compositions for the manufacture of a coarse aggregate-crushed stone, gravel having, for example, the following composition, percent by weight:
(cf. I. I. Moroz "Technology of Building Ceramics", Kiev, Visha Schkola Publishing House, 1972).
However thus-produced concretes have insufficient mechanical strength, since the charge employed for the production of a coarse aggregate has a great amount of dump and burnt rocks and loess.